.......... and there is such a miriad of other things we don't even see or understand that I'm sure they think about in the undoubted meetings they have before they put something out. They may end up wrong sometimes but I would always put my money on them in front of us amateurs taking a punt at a chart that most of us see in some imaginary two dimensional version of the atmosphere. 

 Priceless.

Was hoping the Euro4 would update before bed, but must be another half an hour so to go.

Despite all the gnashing of teeth, parts of the UK are forecast to get lying snow tomorrow. Most notably it is forecast for a part of the country that rarely gets it. https://expert-images.images-weatheronline.com/daten/proficharts/web/en/euro4/2019/01/21/basis12/ukuk/weas/19012306_2112.gif

Could be fairly significant - Merseyside and West Cheshire are not the usual suspects! 

The cold outlook continues on the 18z GFS so far with a NWly cyclone flow dominating again.

Again it is questionable whether the colder than average conditions will be cold enough for widespread wintriness. 

Just for contrasting purposes for fun - temps in N. America - Look at the gradient east/west split@ 336!

Serious question - how can anyone take the "new and improved" GFSP at face value when it clearly initialises with utter garbage parameters?

According to the brand new supercomputers this is the snowcover over the UK at midnight tonight. Either the next 55 minutes are going to be very exciting, or this model is for the bin.

So which is it? Your post says the initialisation is 'utter garbage' and then you say the model is for the bin.

Of course, in fact, it can't be the initialisation because it will be the same as the operational.

Anyway, I don't think I'd condemn a model just because the part that predicts snow cover might need a tweak. Remember the ECM snow cover charts are also unreliable. The precipitation charts show a very brief period of light sleet/snow on the back edge so I'd guess it's the snowcover aspect that is faulty.

Well, I can't find anywhere with snow cover charts at 0 hours for that model. So in that case, to be entirely pedantic, on the NEXT run the initialisation will be garbage if it is assuming that the UK is largely snow covered at that time.

Just been looking again at UKMO thinking how close this is to being a decent chart - if only that runner low could slide into the continent

I don't like the snow run thing much because it doesn't mean a lot. I would point out however that tonight's ensembles give a value of 143 for London. Weren't some of the same people who are now saying cold spell no good getting excited two weeks ago when it hit about 70? 

London 850 Ensembles fairly good cluster around mean now at about -6C from 27th till end of the month which is the limit of the predictable. Maybe not cold enough for widespread snow down here but it will be cold.

Well no, because the initialisation is with actual data (plus estimates for grid points without any observations).

Anyway, your mood seems to have darkened of late?  It’s only a bit of model watching.

Yes, I disregard that statistic.  The theoretical maximum on one ensemble is 1,472 (23x4x16), so even 143 is just about a 10% chance...  Or it could be a day and a half of continuous snow across every perturbation.

Anyway, the ECM 12z ensemble shows the op was right at the top of the suite on Saturday and again near the top on Days 9-10, completely out of line with the mean.

Quite an outlier! The ECM is much warmer this weekend than many other ensembles and yet again, some 5c or so warmer than the mean come day 10. So totally out of sync with others.

No. The theoretical maximum is 23 * 16 = 368.

On that topic (of “snow rows”), for what it’s worth Inverness snow row total is 275 this morning. Generally there’s not much change in the overall outlook this morning with weather from a northwesterly quarter for much of the time, which (especially with elevation) could be wintry for NWern parts.

Elevation wouldn’t really be needed today when the front has cleared for most places, however many places I feel will stay dry.

I think that's a reasonable summary of the NWP. Whether it delivers to low ground in the southern half of the UK is a different question. This type of pattern is like snake oil for southern snow lovers IME.

Or like a teapot made of ice!

It does look as though we have a period of "cold zonality" to look forward to, something which of course brings a greater risk of snow the further north and west you are. January 1984 has often been mentioned as a cold zonal month and that was followed by a not-very-cold easterly setup in February 1984. It remains to be seen whether that's the case this time.

A lot of seriously cold air over eastern Europe, but shows every sign of drifting SE-wards. So until the synoptics change, we will have to rely on the NW-ly flow noted above - good prospects for hill snow in the north, but zilch for the south.

http://www.wxmaps.org/pix/temp4 

The easterlies later on in GFS are (a) in FI like most snow forecast this winter (b) short-fetch, bringing air up from the Mediterranean, not Siberia; cold, but not very cold.

Those charts (from the GFS 00z op data) highlight the cold outlook in the U.K. nicely. Also of note is that week 2 is colder than week 1.

Agreed. Effectively we’re back to the pattern that was emerging a week ago, before the 2-3 day dance with the promise of an easterly.

The phantom easterly had the effect of destroying the calm but upbeat mood in here. Hopefully we can get it back.